The present invention relates generally to primary batteries.
A typical battery (the term battery and cell are interchangably used) includes an outer casing and electrically insulated terminals which together define a sealed interior chamber. Chemically interacting constituents consisting of a cathode, an anode, and electrolyte are located within the chamber for producing a voltage difference of a characteristic value across the terminals.
In cells having a planar arrangement of cathode and anode (electrodes), a problem arises in reliably attaching the electrodes to the terminals.
Part of the problem stems from the fact that the terminal material is usually different than the electrode material. For example, in lithium batteries, the anode is pure lithium metal. The terminals are usually stainless steel or nickel plated steel. And as is well known, dissimilar metals in the presence of an electrolyte form a galvanic cell and internal self discharge occurs.
In prior art lithium cells, lithium metal was pressed onto a stainless steel screen and the screen was spot welded to a stainless steel terminal pin. This approach has the disadvantage of having a large non-lithium anode surface for galvanic action.